Radome structure



March 12, 1963 R. o. ROBINSON, JR

RADOME STRUCTURE Filed March 5, 1959 wnul l hnuu mine mo 9.

momnow zmDhum RALPH 0. RUB/IVSO/V JR.

INvENTdR.

ATTORNEYS 3,8l ,51 Patented Mar. 12, 1963 $381,651 RADGME STRUCTURE Ralph 0. Robinson, 51%, Silver Sepring, Md, assigned to the United States of America as represented by the Secretar-y of the Navy Filed Mar. 5, 1959, Ser. No. 797,553 7 Claims. (63. 244-14) The present invention relates to a radorne for a missile, vehicle or craft and more particularly to the combination of a r adome with a pressure sensing system.

In the flight of missiles, it is necessary to know the force exerted at the forward end of the missile or on the nose of the radome, such as ram pressure or stagnation pressure due to changing speed, altitude or depth of the missile. Prior apparatus for sensing the force and indicating a representation thereof usually requires electrical conductors or air ducts in the walls of the radome for transferring this force representation to missile controlling functions, such as fuel, guidance, safety or aerodynamic ones. However, this requirement of having conductors or ducts in the Walls of the radome aifects the radar transmission properties of the radome by causing discontinuities therein, creating apparent target maneuvers or movements to the intelligence system of the missile.

One of the objects of the present invention is to provide a radome having a pressure sensing system which does not affect the radar transmission qualities of the radome.

An additional object of the present invention resides in the provision of a hydraulic liquid in the structure of a radorne for transferring pressure representation during the flight of a guided missile.

Another object of the present invention is to provide a hydraulic circulation system for measuring pressure exerted on the forward end of a radome.

Still another object of the present invention contemplates incorporating a pressure measuring system in a radome wherein the system exhibits electrical properties equivalent to that of the dielectric material of the radome without affecting the radar transmission properties of the radome.

A further object is to provide hydraulic lines in the structure of a radome in which the electrical properties of the hydraulic fluid used in the hydraulic lines have approximately the same radiant-energy transmission properties as that of the radome material.

ther objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:

FIG. 1 is a block diagram of the pressure measuring system in combination with the radome structure;

FIG. 2 is a cross sectional view of the pressure transducer taken on line 22 of FIG. 1; and

FIG. 3 is a cross sectional view of a modified pressure transducer.

Referring to FIG. 1, of the drawings, a radorne ll(ir1 cross section) is shown for an antenna 14 of a guidable or guided missile, vehicle, or craft. The radome is a dielectric made, for example, from alumina, glass reinforced lamina, or a ceramic material.

The walls 3 of the radome 1 are formed with channels 5 and 6 extending from fittings '7 and 8 to an insert 9 in the nose 4 of the radome. The channels 5 and 6 may be of various cross-section configurations, for example, square or circular. The insert 9 is secured in the nose of the radorne by adhesive, or by other retaining devices such as screw threaded means. The channels 10 and 11 of the insert register with the ends of the channels 5 and 6 in the radome walls. A Well .12 of the insert houses a pressure responsive device or pressure transducer 13, hereinafter described in more detail.

The hydraulic circulating system for supplying hydraulic fluid to the pressure transducer is indicated in FIG. 1 as having a hydraulic source 16, and a hydraulic regulator 17 for maintaining a predetermined rate of liquid flow through theinpu't line 19 to the insert 9 in the nose of the radome. The hydraulic liquid is conveyed from the hydraulic regulator 17 in the input line through the quick disconnect 18 to the fitting and then through channel 5 in the radorne Wall to the insert 9.

The pressure transducer 13 is activated by pressure exerted on the nose of the nadome during the course, or flight of the vehicle and causes variations in the rate of liquid flow through the insert. The hydraulic liquid is returned from the insert 9 through channel 6 in the radome wall to the fitting 8 through the return line 29 and quick disconnect 211 to a flow measurement transducer 22. After the variations in the hydraulic liquid operate the flow transducer, the hydraulic liquid is returned to source 16. However, if necessary, the liquid may be dumped externally of the missile. The flow transducer establishes lfl'OlTl the variations in the rate of liquid flow an electrical Output signal across contacts 24 and 25 representative of pressure exerted on the nose of the radome. This electrical signal is required for the operation of the fuel, guidance, safety or aerodynamic controlling functions of the missile.

The hydraulic lines are provided with the hydraulic quick disconnects '18 and 21 so that the radome 1 may be removed readily without the loss of hydraulic fluid during testing and assembling of the missile.

The insert and pressure transducer are made from a dielectric material having the same qualities as the radorne material so that the transmission of radiant energy through the nose of the radome would not vary from that through the radome walls.

With the development of the present pressure sensing system, a representation of pressure exerted on the nose of the radome is very easily ascertainable. The hydraulic liquid in the circulating system has the same electrical characteristics as the material of the radome walls whereby the transrnission of radiant energy from the antenna 14 is not aflected by the liquid in the radome walls 3. This dielectric characteristic of the hydraulic liquid overcomes the disadvantage of the prior apparatus of using electrical wires or air ducts [for transferring the pressure representation at the nose of the rad'ome. The wires and air ducts caused discontinuities in the radar transmission properties of the radome walls resulting in apparent target errors in the intelligence received and/or transmitted by the steering system of the missile. v

The pressure transducer 13 as shown in FIGS. 1, 2 and 3 is housed within a well 12 of the insert 9. During movement of the craft or vehicle, a force is exerted on the tip 26 of a movable plunger 27. The plunger 27 acts against a quartz or nonmetallic spring 28 which bears against a ledge 29 in the wall 30 of the well. The plunger has a flange 32 with a keyway 33 for fitting a rib or key 34 on the wall of the well providing for a longitudinal displacement of the plunger. The plunger is held within the Well by a screw threaded retaining ring 35 in the mouth of the well.

In the operation of the missile or craft, the force acting on the tip 26 of the plunger is known as ram pres sure. The displacement of the plunger is representative of the pres-sure acting on the plunger. The narrow end 36 of the plunger in FIG. 2 is shown having a triangular shape in cross section. This shape of the plunger end 36 varies the rate or" liquid flow through the insert as a The configuration of the end of the plunger and the crosssectional shape of the orifice of the channel in the insert determines the manner in which the rate of liquid flow varies with pressure. The relationship between pressure and the rate of flow could be a linear, exponential, logarithmic, or any other type of function. Accordingly, any required function of ram pressure could be supplied as an electrical output signal from the flow transducer for the operation of the fuel, aerodynamics, guidance, or safety controls of the vehicle.

In FIG. 3 a modification of the plunger of the pressure transducer is shown. The modified plunger 37 has a transverse channel 33 for registering with the orifice of the hydraulic line 5 or insert channel 10. The particular function of the rate or" liquid flow as it varies wit-h external ram pressure could be determined by various configuration-s of the cross sectional shape of the transverse channel 38 and the hydraulic channels 5 and 6.

Although the invention is indicated as having hydraulic channel input and return lines 5 and 6 in different parts of the radorne, the radome could be made with the hydraulic lines of various cross-sectional configurations and with the input and return channels in the same part of the radome. However, the pressure transducer would be changed accordingly wherein the inlet and outlet orifice of hydraulic channels enter the well of the insert adjacent to each other.

Depending upon how many different functions of pressure are necessary for the operation of various controlling means as the missile or craft changes in speed, altitude or depth, a multiplicity of hydraulic channels could be made in the radome wall. Accordingly, the plunger of the pressure transducer would have a similar multiplicity of differently shaped ends to establish the various functions or" the variation of the rate of liquid flow with a pressure for the flow transducer to transfer as electrical signals to the different controlling means such as fuel, guidance, saLrety or aerodynamic.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope O f the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

l. A pressure responsive device in the nose of a radorne of a missile for measuring the external fiuid pressure exerted on the nose of the radome, comprising a housing with a well, a plunger with a tip and a reduced end, said plunger having a flange between said tip and end, said plunger flange and end being placed within said well, said well having a ledge portion, a spring between said flange and said ledge portion, said plunger .moving against said spring whereby the displacement of said plunger being representative of the pressure exerted on the tip of said plunger and said reduced end of said plunger being capable of varying hydraulic iluid flow through said well.

2. A pressure responsive device as recited in claim 1 wherein the reduced end of said plunger has a cross sectional configuration, whereby movement or" said plunger varies the hydraulic fluid flow through said well as a particular function of the pressure on said plunger tip with the function determined by the cross sectional configuration of the reduced end of the plunger.

3. A pressure responsive device as recited in claim 1 wherein the reduced end of said plunger has a transverse channel, whereby the movement of said plunger varies the hydraulic fluid flow through said well as a particular function of the pressure on said plunger tip with the func tion determined by the cross sectional shape of the transverse channel.

4. In a guidable craft having a radome at its forward end and an electromagnetic wave antenna in said radome, a pressure transducer in the nose of said radome, and a plurality of hydraulic lines communicating with said pressure transducer and formed as integral channels in the walls of said radome and of the same material as said radon-re, the new use in said hydraulic lines of a hydraulic fluid having the same dielectric properties as the walls of said radome whereby radiant energy passing through said radome will not encounter discontinuities due to the presence of said hydraulic fluid in said hydraulic lines.

5. A radome for use in a guidable craft, said radome comprising an ogive-shaped body having walls formed of a dielectric material, a plurality of hydraulic lines integrally formed as channels in the walls of said radome and of the same material as said radome, and a hydraulic fluid in said hydraulic lines, said fluid having dielectric properties duplicating those of the dielectric material constituting the walls or" said radorne.

6. A radorne for use in a guidable craft, said radome comprising an ogive-shaped body having walls formed of a dielectric material, a plurality of hydraulic lines integrally formed as channels in the walls of said radome, and a hydraulic fluid in said hydraulic lines, said hydraulic lines and hydraulic fluid having dielectric properties duplicating those of the dielectric material constituting the walls of said radome, whereby radiant energy passing through said radorne will not encounter discontinuities due to the presence of said hydraulic lines or of hydraulic fluid in said hydraulic lines.

7. in a guidable aircraft, a radome comprising an ogiveshaped body having walls formed of a dielectric material, a pressure transducer in the nose of said radome, a plurality of hydraulic lines integrally formed as channels in the walls of said radome and communicating with said pressure transducer, and a hydraulic fluid in said hydraulic lines, said hydraulic lines and hydraulic fluid having dielectric properties duplicating those of the dielectric material constituting the walls of said radome, whereby radiant energy passing through said radcme will not encounter discontinuities due to the presence of said hydraulic lines or of hydraulic fluid in said hydraulic lines. 

1. A PRESSURE RESPONSIVE DEVICE IN THE NOSE OF A RANDOME OF A MISSILE FOR MEASURING THE EXTERNAL FLUID PRESSURE EXERTED ON THE NOSE OF THE RADOME, COMPRISING A HOUSING WITH A WELL, A PLUNGER WITH A TIP AND A REDUCED END, SAID PLUNGER HAVING A FLANGE BETWEEN SAID TIP AND END, SAID PLUNGER FLANGE AND END BEING PLACED WITHIN SAID WELL, SAID WELL HAVING A LEDGE PORTION, A SPRING BETWEEN SAID FLANGE AND SAID LEDGE PORTION, SAID PLUNGER MOVING AGAINST SAID SPRING WHEREBY THE DISPLACEMENT OF SAID PLUNGER BE- 